GM Duramax Diesel CP4 Fuel Pump Lawsuit Certified In Seven States36
A lawsuit against GM has been certified as a class action for General Motors customers in seven U.S. states. The lawsuit affects customers who own Chevy Silverado and GMC Sierra pickup trucks equipped with the 6.6L V8 LML turbodiesel Duramax engine. According to the lawsuit, the Bosch CP4 fuel pump on these engines is defective.
Per a report from Car Complaints, the lawsuit alleges that 2011- through 2016-model-year Chevy Silverado and GMC Sierra pickups equipped with the 6.6L V8 LML turbodiesel Duramax engine are equipped with defective Bosch CP4 fuel pumps that are more fragile and prone to wear than previous CP3 fuel pumps. According to plaintiffs, the defective CP4 pumps can be destroyed by U.S. diesel fuel, which is allegedly “drier” than diesel fuel in other countries.
The lawsuit alleges that U.S. diesel fuel does not provide adequate lubrication for the CP4 fuel pump. The lack of lubrication can lead to internal fuel pump damage and result in metal shavings that damage the pump, the fuel system, and the GM Duramax engine as well. This damage can lead to the truck stalling and losing power, and may require the vehicle to be towed to a shop, leaving customers with big repair bills.
The lawsuit goes on to allege that GM was aware that the Duramax engines and related fuel pumps were defective prior to selling affected vehicles, but declined to notify customers. Rather, GM allegedly concealed that the defective CP4 pumps may be destroyed by U.S. diesel fuel.
Now, the new lawsuit has been certified as a class action for customers in California, Florida, Illinois, Iowa, New York, Pennsylvania, and Texas. The lawsuit was filed in the U.S. District Court for the Eastern District of Michigan (Southern Division), while plaintiffs are represented by The Miller Law Firm, P.C., Hagens Berman Sobol Shapiro LLP, and Hilliard Martinez Gonzalez LLP.
As GM Authority covered previously, GM’s motion to dismiss the lawsuit in California was rejected.
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I consistently add Lucas to my fuel system when I fuel up to prevent this from occurring. Shouldn’t have to, but the “low sulfer” diesel made for US emissions isn’t healthy for a CP4.
Me to Mike seems to be working
Shame on GM ! Wrong headed and wrong direction for this. ALl my family owns is Chevrolet trucks and two classic cars. Two of the trucks are diesels one is an LML. The AFM engie in our 2009 is garbage and the top end was replaced at my cost at 80k. Worst design ever until the CP4. Look at your heads of departments GM, the decisions they are making are not in your best interest. Replace the Cp4’s like Dodge or you will see loyal Americans switching to them.
GM did abandon the CP4 pump in favor a much better Denso unit. GM, Ford and Ram were all using the CP4 pump at one time.
GM was the first to abandon the CP4, followed by Ram who went back to the CP3 and Ford still uses this defective pump to this day.
Lawsuit should be against Bosch
CP3 to CP4, “fix what’s not broke”. I’ll bet the CP4 was cheaper to manufacture. Happens all the time. Another case, the GM ignition switch redesign that killed many in collisions because it switched off the air bags. What was wrong with the previous switch? Nothing!
So, I’m very sorry for the past and present expensive repairs incurred with any individuals. For the rest of us, some with lower mileage on our vehicles 6.6 are just waiting and praying that no damage or breakdowns occur in the middle of a family trip, leaving us helpless, and unable to afford the time and high expenses of a off road repair. This is what a genuine recall is all about.it is not the customers fault, but the companies. So for now, we ride in ticking time bombs. WTF….
All you have to do for a mostly reliable lml is install a lift pump either airdog or fass ( airdog is my preference ) and also install a exergy fuel system saver. The lift pump will in most cases save the cp4 from being destroyed by keeping the fuel system pressurized so no air can get to the cp4 and it also removes water from the system and the exergy fuel system saver will in most cases catch the metal shavings if the cp4 still decides to grenade which at that point you can do a cp3 conversion and only have swap the pump instead of the whole fuel system.
One of the reasons I went with the duramax was for life longevity of the engine paired with the allison transmission.
I have just over 100k miles on my Silverado and I’m at the milestone where sh#t seems to happen with the CP4 for a lot of trucks. Now I’m afraid to take the truck on long trips, and in the back of my mind I’m always wondering when the CP4 will grenade. From what I’ve read the repair cost can approach $15k. GM and/or Bosch should be held accountable.
100,000 miles, change the fuel pump now.
If you have one put a Fass or Air Dog on it just to protect your truck if you love your truck, I miss mine. The factory located fuel filters are junk as well if you go by their filtration numbers, if I went out west I came back with grit in my injector from the sand in the barges they bring diesel in with. You don’t want to inspect the tanks in the barges and trucks they haul your diesel in. I took all precautions and maintained regularly because my business depended on it, Russian Roulette is what I was playing unknowingly east coast diesel is a little easier on them but not much.
Hello all I have a 2019 diesel and my pump just went out. Quotes are $12-20k. I have to replace the whole fuel system with all new injectors. Funny thing is I own a dodge also but they recalled their cp4 pumps.
I’m pretty sure the 2019 does not have a Cp4
GM stopped using the cp4 in 2016. The 2017 and above duramax’s use the new Denso pump. If you have a 19 and your pump went that’s the first I’ve heard of a Denso pump going.
some blame should be given to the oil companies for making bare minimum diesel fuel and to the gov’t for allowing such poor quality fuel to be made. it’s part of the reason we don’t get as many diesel vehicles here. Tough emission laws and garbage fuel. tough combo to beat.
Actually, the US Government didn’t ALLOW the bad diesel fuel, they REQUIRED it. The process of making low sulfur diesel removed the lubricity of the fuel.
When we switched to unleaded gasoline, the lead was a lubricant for the valves. Engines had to be manufactured with harder seats and valve seals.
True but the oil companies could be putting a lubricant back into the diesel fuel but they don’t. So therefore I do I use Hotshot secret everyday diesel treatment it’s been proven by many tests to provide the lubrication that is needed for the cp4 pump.
Most of the blame lands on GM. While Ford and Cummins are certainly not immune to the pump failure……they also have a lift pump supplying pressurized fuel to the CP4. Typical GMC in there smart cost saving decide to run the CP4 as a lift pump AND pressure pump. We all know how long the Cummins 24 valve 5.9 injection pumps run for after the lift pump fails. I remember installing aftermarket low pressure systems to tell us if the lift pump fails as the engine will run fine till the injection pump dies. Root cause on alot of them, failed OEM lift pumps.
That’s very correct jimmy.
My C4 just went on mine and had to be towed. No have to replace everything costing thousands.
Does this mean that because the lawsuit was certified in 7 states that people that own these trucks in a state not included can’t join the lawsuit?
My question exactly! Just got our 2015 Silverado back from the shop. Total cost was $13,025.43. We’re in Colorado Springs, Colorado… What about us???
Yes the 2019 has the CP4.
They need to get this lawsuit kicked in gear in Ohio. My 2013 cp4 is on its way out now. Still runs but in limp mode and low fuel rail pressure. Fluctuating idle and extremely noisy pump. As much as we pay for these trucks the repairs should be minimal.
CP4 has been trash since it came out. It is not made for the U.S. Every truck owner that has this Pump takes extra steps to make sure that pump doesn’t fail on them. We shouldn’t have to.
Damnest thing..I just smoked a tater in the tool shed fore I headed over to grab ICEE at the Kmart and ask brunette if she wanted to try out my new water bed the CP4 went OUT! I’m goin back to the 06
How or who do you contact about this law suit? I have a 2015 LML with CP4 also
Geometrically the CP4 pump is more efficient. Wish Bosch had made it equally as durable. I know that GM validation tests use various imported fuels to run durability/validation tests. Can’t believe that Bosch and GM missed this.
I can only assume that the cost/benefit study of warranty liability justified the CP4 usage.
Bet they didn’t count on a class action suit in that analysis!
Been using stanadyne lubricity additive since day 1.
2012 LML 31k. DEF pump and DEF injector failure at 30k. Steering box seal blown out at same time. $4,500 to fix both.
My fuel pump on my 2016 craped out at 90000 miles leaving me with a 12000 bill for repairs having to replace fuel rail injectors and the fuel pump. also have a 2013 silverado had the same issue decided to buy a used duramax and swaped it out all total roughly around 11000 dollars again will not by another GM diesel engine for any price.
While it was still working, I replaced my LMLs CP4 around 50,000 miles with a emissions compliant CP3, and recently added a single Kennedy lift pump. All to increase reliability and avoid a catastrophic and costly repair. Any part can fail, but when it fails like the CP4 does by destroying most if not all of the rest of the fuel delivery system in the process, that is simply not acceptable.
Perhaps gas is the way to go